Lennon was the direct inspiration for three Beatles' songs: "Lucy in the Sky with Diamonds", "Hey Jude" and "Good Night". He is devoted to philanthropic endeavors, most notably his own White Feather Foundation[3] and the Whaledreamers Organization,[4] both of which promote the co-existence of all species and the health and well-being of the Earth.

Julian Lennon was born in Liverpool. Initially, the fact that John Lennon was married and had a child was concealed from the public, in keeping with the conventional wisdom of the era that female teenage fans would not be as enamoured of married male pop stars. Lennon inspired one of his father's most famous songs, "Lucy in the Sky with Diamonds", whose lyrics describe a picture the boy had drawn, a watercolour painting of his friend Lucy O'Donnell from nursery school[5] surrounded by stars. Another composition of his father inspired by him was the lullaby "Good Night", the closing song of the White Album. In 1967, he attended the set of the Beatles' film Magical Mystery Tour.

Following his father's infidelity with Yoko Ono, Lennon's parents divorced when he was five. Paul McCartney wrote "Hey Jude" to console him over the divorce; originally called "Hey Jules", McCartney changed the name because he thought that "Jude" was an easier name to sing.[6] After his parents' divorce, Lennon had almost no contact with his father until the early 1970s when, at the request of his father's then short-term girlfriend, May Pang (Yoko Ono and Lennon had temporarily separated), he began to visit his father regularly. John Lennon bought him a Gibson Les Paul guitar and a drum machine for Christmas 1973, and encouraged his interest in music by showing him some chords.[7][8]

I've never really wanted to know the truth about how dad was with me. There was some very negative stuff talked about me ... like when he said I'd come out of a whiskey bottle on a Saturday night. Stuff like that. You think, where's the love in that? Paul and I used to hang about quite a bit ... more than Dad and I did. We had a great friendship going and there seems to be far more pictures of me and Paul playing together at that age than there are pictures of me and my dad.[9]

Lennon was also irked by hearing his father's peace-loving stance perpetually celebrated. He told the Daily Telegraph, "I have to say that, from my point of view, I felt he was a hypocrite", he said, "Dad could talk about peace and love out loud to the world but he could never show it to the people who supposedly meant the most to him: his wife and son. How can you talk about peace and love and have a family in bits and pieces—no communication, adultery, divorce? You can't do it, not if you're being true and honest with yourself."[10]

Lennon was excluded from his father's will. However, a trust of £100,000 was created by his father to be shared between all of his children (both Julian and Sean).[11][12] Julian sued his father's estate and in 1996 reached a settlement agreement reportedly worth £20 million.[11] By 2009, Lennon's feelings toward his father had mellowed. Recalling his renewed relationship with his father in the mid-1970s, he said,

Dad and I got on a great deal better then. We had a lot of fun, laughed a lot and had a great time in general when he was with May Pang. My memories of that time with Dad and May are very clear — they were the happiest time I can remember with them.[13]

In 2007, Lennon sold a "significant" share of his stake in his father's catalogue of work[14] in exchange for an undisclosed sum with an agreement that the purchasing company, Primary Wave, would market and promote his new material. The stake entitles Primary Wave to a portion of all royalties on the catalogue.

Lennon made his musical debut at age 11 on his father's album Walls and Bridges playing drums on "Ya-Ya", later saying, "Dad, had I known you were going to put it on the album, I would've played much better!"[16] In the 1980s, he “parlayed a remarkable vocal similarity to his father into a successful singing career.” [17]

Lennon enjoyed immediate success with his debut 1984 album Valotte, produced by Phil Ramone, nominated for a Grammy Award for Best New Artist in 1985, spawning two top ten hits, the title track "Valotte" and "Too Late for Goodbyes". Lennon promoted the album with music videos for the two hits made by movie director Sam Peckinpah and producer Martin Lewis. The song "Valotte" has remained a staple on adult contemporary radio stations since its release.

After the release Paul McCartney sent him a telegram wishing him good luck. Later that year the two met backstage at the New York studios of the television show Friday Night Videos.

He recorded the song "Because", previously recorded by The Dave Clark Five, in the UK for Clark's 1986 musical, Time. Lennon never reached the same level of success in the U.S. post-Valotte, but he hit No. 5 in Australia with the 1989 single "Now You're In Heaven", which also gave him his second No. 1 hit on the Album Rock Tracks chart in the USA.

By the end of the year, Lennon left the music business for several years. He followed his interests in cooking, sailing, and sculpting during his leave from the music industry. After he began his performing career there was occasionally unfounded media speculation that Julian would undertake performances with Paul McCartney, George Harrison and Ringo Starr. However, in the Beatles Anthology series in 1996, the three surviving Beatles confirmed there was never an idea of having Julian sit in for his father as part of a Beatles reunion, with McCartney saying, "Why would we want to subject him to all of this?"

In 2006 he ventured into Internet businesses, including MyStore.com with Todd Meagher and Bebo founder Michael Birch.[21] In 2009 Lennon created a new partnership with Todd Meagher and Michael Birch called theRevolution, LLC. Through this company, Lennon released a tribute song and EP, "Lucy", honoring the memory of Lucy Vodden (nee O'Donnell), the little girl who inspired the song "Lucy in the Sky with Diamonds", with 50 percent of the proceeds going to fund Lupus research.[22][23][24]

In 2012 Lennon worked with music film director Dick Carruthers on the feature length video documentary "Through The Picture Window", which followed Lennon's journey in the making of his album Everything Changes and includes interviews with Steven Tyler, Bono and Paul Buchanan from The Blue Nile. "Through The Picture Window" was also released as an App in all formats with bespoke videos for all 14 tracks from the album.[25][26][27]

Julian Lennon is also the producer of the documentary called WhaleDreamers[29] about an aboriginal tribe in Australia and its special relationship to whales. It also touches on many environmental issues. This film has received many awards[30] and was shown at the 2007 Cannes Film Festival.

After photographing his half-brother Sean's music tour in 2007, Lennon took up a serious interest in photography.[31]

On 17 September 2010,[32] Lennon opened an exhibition of 35 photographs called "Timeless: The Photography of Julian Lennon" with help from long-time friend and fellow photographer Timothy White. Originally scheduled to run 17 September through 10 October,[33] the Morrison Hotel Gallery extended it a week to end 17 October.[34] The photographs include shots of his half-brother Sean, actress Kate Hudson, and U2 frontman Bono.[31]

On 3 October 2010, CBS Sunday Morning aired an in-depth interview with Lennon that covered much of his life, including his relationship with his parents and sibling, his career, and his experience growing up as the son of one of the world's most famous celebrities.[35]

Lennon's "Horizons" series is featured at the Emmanuel Fremin Gallery, NYC, 12 March – 2 May 2015.[36]

Lennon founded The White Feather Foundation in 2009. Its mission "embraces environmental and humanitarian issues and in conjunction with partners from around the world helps to raise funds for the betterment of all life, and to honour those who have truly made a difference."[38] Its name came from a conversation Lennon once had with his father. "Dad once said to me that should he pass away, if there was some way of letting me know he was going to be OK – that we were all going to be OK – the message would come to me in the form of a white feather. ... the white feather has always represented peace to me."[39]

Lennon has been quoted as having a "cordial" relationship with Ono while getting along very well with her son, his half-brother Sean. Lennon saw Sean perform live for the first time in Paris on 12 November 2006 at La Boule Noire [40] and he and Sean spent time together on Sean's tour in 2007. In commemoration of John Lennon’s 70th birthday and as a statement for peace, Lennon and his mother, Cynthia, unveiled the John Lennon Peace Monument in his home town of Liverpool, England, on 9 October 2010.[41]

Lennon has been engaged twice – to socialite Lucy Bayliss and actress Olivia d'Abo - but both engagements were called off.[42] He now resides near Monaco.

Lennon remains friends with his father's former bandmate, McCartney, though they experienced a public falling out in 2011 when Lennon was not invited to McCartney's wedding to Nancy Shevell.[43]

Top 100 (Kent Music Report) singles and albums peaks until 19 June 1988: Kent, David (1993). Australian Chart Book 1970–1992 (Illustrated ed.). St Ives, N.S.W.: Australian Chart Book. p. 176. ISBN0-646-11917-6. N.B. The Kent Report chart was licensed by ARIA between 1983 and 19 June 1988.